Neuronal and peripheral cell receptors that bind the neurotransmitter serotonin constitute a group of at least seven structurally distinct proteins that can now be produced using recombinant-DNA techniques. These techniques have been applied to construct cell lines that incorporate the serotonin receptor in their membranes, to provide a valuable, regenerable and homogeneous source of substrate with which chemical libraries can be screened to identify potential CNS-active drugs.
Recent evidence strongly implicates the serotonin receptor classified as 5-HT2 in the etiology of such medical conditions as hypertension, thrombosis, migraine, vasospasm, ischemia, depression, anxiety, schizophrenia, sleep disorders and appetite disorders. It has been suggested that compounds capable of interfering with the function of this receptor, particularly when there is an excess of circulating serotonin, would be useful to treat these conditions (see U.S. Pat. No. 4,931,447 and WO 94/02462). However, the tendency for ligands to bind indiscriminately to various types of dopamine receptors, such as the dopamine D4 and D2 receptors, has made difficult the development of drugs that are 5-HT2 receptor-selective. It would nevertheless be desirable to provide such a compound, particularly so that side effects are minimized during treatment of the conditions noted above.
It is an object of the present invention to provide a compound having an improved 5-HT2 receptor selectivity profile.
It is a further object of the present invention to provide a pharmaceutical composition comprising a compound of the present invention, as active ingredient.